The 1980 National Natality Survey and 1980 National Fetal Death Survey conducted by the National Center of Health Statistics (NCHS) contains data on 9,941 live births and 6,386 fetal deaths. For each live birth and fetal death certificate selected, a mother, physician, hospital and radiation questionnaires was obtained by NCHS. This project will provide data on a nationwide sample relating to pregnant women's characteristics, outcome of pregnancy, labor and delivery.